Design work started in 1942 regarding Archer, a self-propelled anti-tank weapon intended as a stopgap until a full-time solution could possibly be discovered. Mounting the gigantic 17 pounder gun on reasonably small Valentine infantry tank framework was challenging which the Archer's developers met with a unique solution - setting up the gun back-to-front, aided by the fighting compartment trying out leading for the car. Making use of armor-piercing rounds, it might beat 192mm of armor at 914 meters, sufficient to pose ample risk to any German armor of this time. Production started in 1944, and Archers were delivered to the British Army's Armoured and Infantry Divisions, who began using it from October.